Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability
Supraglacial lakes play an important role in establishing hydrological connections that allow lubricating seasonal meltwater to reach the base of the Greenland Ice Sheet. Here we use new surface velocity observations to examine the influence of supraglacial lake drainages and surface melt rate on ic...
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ftunivnewcastle:oai:eprint.ncl.ac.uk:195617 2023-05-15T16:28:52+02:00 Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability Joughin I Das SB Flowers GE Behn MD Alley RB King MA Smith BE Bamber JL van den Broeke MR van Angelen JH 26-07-2013 application/pdf https://eprint.ncl.ac.uk/fulltext.aspx?url=195617/6BB6320C-553B-49C3-8219-07A1E8F30B7C.pdf&pub_id=195617 unknown Copernicus GmbH Cryosphere, 26-07-2013 Article 2013 ftunivnewcastle 2020-06-11T23:21:16Z Supraglacial lakes play an important role in establishing hydrological connections that allow lubricating seasonal meltwater to reach the base of the Greenland Ice Sheet. Here we use new surface velocity observations to examine the influence of supraglacial lake drainages and surface melt rate on ice flow. We find large, spatially extensive speedups concurrent with times of lake drainage, showing that lakes play a key role in modulating regional ice flow. While surface meltwater is supplied to the bed via a geographically sparse network of moulins, the observed ice-flow enhancement suggests that this meltwater spreads widely over the ice-sheet bed. We also find that the complex spatial pattern of speedup is strongly determined by the combined influence of bed and surface topography on subglacial water flow. Thus, modeling of ice-sheet basal hydrology likely will require knowledge of bed topography resolved at scales (sub-kilometer) far finer than existing data (several km). Article in Journal/Newspaper Greenland Ice Sheet Newcastle University Library ePrints Service Greenland |
institution |
Open Polar |
collection |
Newcastle University Library ePrints Service |
op_collection_id |
ftunivnewcastle |
language |
unknown |
description |
Supraglacial lakes play an important role in establishing hydrological connections that allow lubricating seasonal meltwater to reach the base of the Greenland Ice Sheet. Here we use new surface velocity observations to examine the influence of supraglacial lake drainages and surface melt rate on ice flow. We find large, spatially extensive speedups concurrent with times of lake drainage, showing that lakes play a key role in modulating regional ice flow. While surface meltwater is supplied to the bed via a geographically sparse network of moulins, the observed ice-flow enhancement suggests that this meltwater spreads widely over the ice-sheet bed. We also find that the complex spatial pattern of speedup is strongly determined by the combined influence of bed and surface topography on subglacial water flow. Thus, modeling of ice-sheet basal hydrology likely will require knowledge of bed topography resolved at scales (sub-kilometer) far finer than existing data (several km). |
format |
Article in Journal/Newspaper |
author |
Joughin I Das SB Flowers GE Behn MD Alley RB King MA Smith BE Bamber JL van den Broeke MR van Angelen JH |
spellingShingle |
Joughin I Das SB Flowers GE Behn MD Alley RB King MA Smith BE Bamber JL van den Broeke MR van Angelen JH Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
author_facet |
Joughin I Das SB Flowers GE Behn MD Alley RB King MA Smith BE Bamber JL van den Broeke MR van Angelen JH |
author_sort |
Joughin I |
title |
Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
title_short |
Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
title_full |
Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
title_fullStr |
Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
title_full_unstemmed |
Influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
title_sort |
influence of ice-sheet geometry and supraglacial lakes on seasonal ice-flow variability |
publisher |
Copernicus GmbH |
publishDate |
2013 |
url |
https://eprint.ncl.ac.uk/fulltext.aspx?url=195617/6BB6320C-553B-49C3-8219-07A1E8F30B7C.pdf&pub_id=195617 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
Cryosphere, 26-07-2013 |
_version_ |
1766018557811884032 |